Live birth in Cretaceous marine lizards (mosasauroids)

@article{Caldwell2001LiveBI,
  title={Live birth in Cretaceous marine lizards (mosasauroids)},
  author={Michael Wayne Caldwell and M S Lee},
  journal={Proceedings of the Royal Society of London. Series B: Biological Sciences},
  year={2001},
  volume={268},
  pages={2397 - 2401}
}
  • M. Caldwell, M. S. Lee
  • Published 7 December 2001
  • Environmental Science, Geography
  • Proceedings of the Royal Society of London. Series B: Biological Sciences
Although live-bearing (viviparity) has evolved around 100 times within reptiles, evidence of it is almost never preserved in the fossil record. Here, we report viviparity in mosasauroids, a group of Cretaceous marine lizards. This is the only known fossil record of live-bearing in squamates (lizards and snakes), and might represent the oldest occurrence of the trait in this diverse group; it is also the only known fossil record of viviparity in reptiles other than ichthyosaurs. An exceptionally… 
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TLDR
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